Bottom Line:
We found that miR-200a was downregulated in HCC/SP and this was associated metastasis.Overexpression of miR-200a in SP cells decreased metastasis-related markers and expression of ZEB2.The associations between miR-200a, SP cells and ZEB2 were validated in HCC.

Affiliation: Department of Hepatobiliary Surgery, The Xijing Hospital of The Fourth Military Medical Uiversity, Xi'an, China.

ABSTRACTAlthough microRNA-200a (miR-200a) is frequently downregulated in cancer, its role in side population (SP) has not been investigated. In this study, 101 pairs of primary hepatocellular carcinoma (HCC) tissues and matched normal control tissues were analyzed for miR-200a expression and its clinicopathological value was determined. We found that miR-200a was downregulated in HCC/SP and this was associated metastasis. MiR-200a suppressed metastasis of SP cells. Overexpression of miR-200a in SP cells decreased metastasis-related markers and expression of ZEB2. The associations between miR-200a, SP cells and ZEB2 were validated in HCC. These findings reveal that miR-200a suppresses metastasis of SP cells by downregulating ZEB2.

Figure 4: Characteristic of SP and NSP cells(A) The expression of ALBU (a marker of mature hepatocytes) and KRT14 (a marker of liver stem cells) in side population cells and in non-side population cells that were isolated from HCC cell lines. (B) Sphere formation assay: SP and non-SP cells were cultured in serum-free media for two weeks (magnification×100). (C) Cell invasion and migration assays: (Left panel, representative images of migration assay and quantification of cell number; Right panel, representative images of invasion assay and quantification of cell number). (D) Images of cells stained with Rhodamine Phalloidin and DAPI reflect the different morphologies (magnification×400). *p < 0.05, **p < 0.01, t test.

Mentions:
ALBU, a marker of mature hepatocytes, was lower in SP cells and higher in non-SP cells. Conversely, KRT14, a marker of liver stem cells, was highly expressed in SP cells but was weakly expressed in NSP cells (Fig. 4A). The number of spheres formed by SP cells from the Huh7 and MHCC-97H cell lines was significantly higher than the corresponding number of NSP cells. In addition, the SP cells were able to induce larger spheres than the non-SP cells (Fig. 4B).

Figure 4: Characteristic of SP and NSP cells(A) The expression of ALBU (a marker of mature hepatocytes) and KRT14 (a marker of liver stem cells) in side population cells and in non-side population cells that were isolated from HCC cell lines. (B) Sphere formation assay: SP and non-SP cells were cultured in serum-free media for two weeks (magnification×100). (C) Cell invasion and migration assays: (Left panel, representative images of migration assay and quantification of cell number; Right panel, representative images of invasion assay and quantification of cell number). (D) Images of cells stained with Rhodamine Phalloidin and DAPI reflect the different morphologies (magnification×400). *p < 0.05, **p < 0.01, t test.

Mentions:
ALBU, a marker of mature hepatocytes, was lower in SP cells and higher in non-SP cells. Conversely, KRT14, a marker of liver stem cells, was highly expressed in SP cells but was weakly expressed in NSP cells (Fig. 4A). The number of spheres formed by SP cells from the Huh7 and MHCC-97H cell lines was significantly higher than the corresponding number of NSP cells. In addition, the SP cells were able to induce larger spheres than the non-SP cells (Fig. 4B).

Bottom Line:
We found that miR-200a was downregulated in HCC/SP and this was associated metastasis.Overexpression of miR-200a in SP cells decreased metastasis-related markers and expression of ZEB2.The associations between miR-200a, SP cells and ZEB2 were validated in HCC.

Affiliation:
Department of Hepatobiliary Surgery, The Xijing Hospital of The Fourth Military Medical Uiversity, Xi'an, China.

ABSTRACTAlthough microRNA-200a (miR-200a) is frequently downregulated in cancer, its role in side population (SP) has not been investigated. In this study, 101 pairs of primary hepatocellular carcinoma (HCC) tissues and matched normal control tissues were analyzed for miR-200a expression and its clinicopathological value was determined. We found that miR-200a was downregulated in HCC/SP and this was associated metastasis. MiR-200a suppressed metastasis of SP cells. Overexpression of miR-200a in SP cells decreased metastasis-related markers and expression of ZEB2. The associations between miR-200a, SP cells and ZEB2 were validated in HCC. These findings reveal that miR-200a suppresses metastasis of SP cells by downregulating ZEB2.